Three-dimensional (3D) images exist today in many different digital formats. The number of different formats together with the apparent lack of standardization for formatting such 3D images leads to many problems and further complexities in recognizing the presence of such 3D images and then in determining how the 3D image is formatted in order to process and display the image properly.
Generally 3D contents include a pair of images or views initially generated as separate stereo images (or views). It will be appreciated that the terms “stereo images” and “stereo views” and the terms “images” and “views” may each be used interchangeably without loss of meaning and without any intended limitation. Each of these images may be encoded. In order to store or distribute or display the 3D image, the contents of the two stereo images are combined into a single image frame. So each frame will represent the entire 3D image instead of using two separate stereo images, each in their own frame or file. Various formats for such a 3D image frame are depicted simplistically along the top row of FIG. 1.
As seen from FIG. 1, many 3D image frame formats exist today and it is expected that additional formats will be suggested in the future. Some 3D image frame formats include a side-by-side format, a checkerboard pattern format, an interlaced format, a top-bottom format, and a color based format such as an anaglyph. All but the color based format are shown in simplified form in FIG. 1. In this figure, one of the stereo images or stereo views of a 3D image is depicted in light shading, while the second image or view associated with that 3D image is depicted in dark shading. The ability to support multiple frame formats for 3D images will be important for the success of 3D products in the marketplace.
One problem that arises by generating 3D image files in these single frame formats is that the resulting single image frame without further analysis may appear similar to an image frame used for a non-stereo image or a two-dimensional (2D) image. Moreover, a stream of such 3D image frames may initially appear indiscernible from a stream of 2D image frames. When the format and dimensionality of the image frame is not known or communicated to a receiver, significant and as yet unsolved problems arise for image viewers, video players, set-top boxes, and the like, which are used for receiving, processing, and displaying the contents of the image frame stream.
Nowhere has the prior art in this technical field shown an ability to distinguish a single stereo image in 3D formats from a non-stereo single image. Moreover, the prior art in this technical field has similarly failed to show an ability to identify that an image file is in one particular format out of a plurality of possible 3D and 2D formats.